TRD's General Explanation of Suspensionhttp://www.trdusa.com/GeneralInformation.asp...
Lowering Springs - The key to good handling is a well-tuned suspension. The components that actually do the "suspending" are the springs. All else being equal, a stiffly-sprung vehicle handles better than one with softer springs. In the real world of highway driving, stiff springs, which are great for handling, provide too harsh of a ride, and soft springs for comfort don't provide the handling enthusiasts demand. As a solution, TRD offers progressive-rate coil springs. Over irregular road surfaces, the lower-rate coils of a progressive-rate spring compress first allowing a more compliant, softer ride. As the force on the spring increases, like when rounding a corner, the higher-rate coils provide a progressively stiffer ride. The result is better handling and a tighter grip with little compromise in ride quality. And, lowered cars look better and faster. TRD offers a wide variety of progressive-rate springs so you can select the right spring package to fit your needs. Some are designed to work with your vehicle's stock suspension while others are designed to work in conjunction with other TRD high-performance suspension components. All TRD coil springs are manufactured from high quality chrome-silicon wire and powder coated, and all are designed to lower the vehicle, usually from 1" to 1.125".
Shock Absorbers and Struts - Shocks/Struts work in conjunction with springs to control the interaction between your car's wheels and its chassis and reduce the amount of force that shuttles back and forth between them. The result is a more consistent and comfortable driving experience. Purchasing the right high-performance shock absorber for your vehicle is critical to dampening the forces that impact your car every day - keeping you and your car in control of the road. TRD, together with some of the most highly regarded shock/strut manufacturers in the worked, has engineered the ideal performance suspension system for your Toyota. With more aggressive valving and a higher dampening rate than OE, TRD shocks/struts improve handling, steering response and cornering power. The monotube construction allows the working cylinder direct air exposure which reduces the amount of heat build-up in the shock. Additionally, TRD shocks/struts are nitrogen gas-charged to eliminate oil foaming and provide consistent operation over a wide range of temperatures and conditions. TRD lowering springs are highly recommended for use with our high-performance shocks/struts.
Sway Bars - Performance sway bars provide the most significant upgrade in suspension handling per dollar than virtually any other suspension modification available. Stock sway bars are a good compromise for everyday driving conditions, but for performance driving, they are simply not stiff enough. Stiffer sway bars provide increased roll stiffness, reducing body roll for improved handling and steering response. TRD sway bars range from 25 to 100 percent stiffer than stock. The result is improved traction and more controlled turns without compromising ride quality. TRD has both front and rear sway bars available depending on application. Stiffer bracket bushings are also included in some sets.
Coil-Over Suspension - Any stock suspension system is limited in its adjustability. Upgrading your springs and struts alone may never allow you to achieve your vehicle's ultimate suspension set-up. The TRD racing-style coil-over suspension is a no-compromise performance suspension system. Virtually every facet of your vehicle's suspension performance can be adjusted to suit a wide range of requirements. Drop it to the ground at the Saturday afternoon autocross, and crank it back up for the ride home. With TRD coil-overs, precise tuning of rebound and compression dampening, ride height, roll center and spring rate are possible. TRD coil-over suspension units come equipped with medium rate springs that are suitable for most street applications. Springs of varying rates are available separately (contact your TRD technical representative for additional information.) TRD coil-overs units are designed to replace stock strut assemblies and mount in the original strut location.
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TRD's sport parts and merchandise are marketed and sold through Toyota dealerships nationwide. TRD only markets the highest quality parts and merchandise, consistent with the Toyota image and customer expectations.
